Encapsulated dispersions comprising electrophoretically mobile organic colorants

US8040592B2 · kind B2 · utility

Assignee

• BASF SE

Inventors

• Margherita Fontana · Basel, CH
• Gerardus De Keyzer · Riehen, CH
• Philippe Bugnon · Le Mouret, CH
• Marcel Hahn · Magden, CH
• Kishor Kumar Mistry · Heysham, GB
• Clemens Auschra · Glückstadt, DE

Key dates

• Filing date: Jun 27, 2007
• Grant date: Oct 18, 2011
• Expiry date: Feb 22, 2028

Classification

• Technology area (CPC G): Physics
• CPC primary: G02F1/167
• WIPO field: Optics
• WIPO sector: Instruments

Abstract

The invention relates to an electrophoretic display, comprising electrodes and cells containing at least one kind of ionic, monochrome particles, a non-polar liquid and a dispersant, wherein the ionic, monochrome particles of at least one kind are essentially aggregates consisting of a carbon containing pigment and an anionic pigment or anionic pigment derivative, and the dispersant is selected from the group consisting of polyacrylates, polyesters, polyurethanes and copolymers. In general, the whole quantity of the pigment and the main part, preferably at least 80%, most preferred from 95% to 100%, of the whole anionic pigment or anionic pigment derivative present within the cells is comprised in the aggregates, with essentially no pigment and only a minor part of the anionic pigment or anionic pigment derivative physically distinct from the aggregates.